The judge presiding over Prince Harry's case against Mirror Group Newspapers (MGN) told the Duke's lawyer to show evidence during his closing statement.
Mr Justice Fancourt made the comments while listening to David Sherborne was giving his closing speech.
He said to the barrister, who is also representing three other high-profile claimants as well as the Duke of Sussex, to "show me the evidence, not just assertions by you".
The judge told Sherborne: "Give me your best two examples of particular evidence that Prince Harry was able to give of a particular message."
MGN is being sued by several high-profile people over alleged unlawful information gathering at its titles.
PA
In response, the Duke's barrister highlighted Harry's witness statement, telling the court that "when he deals with the articles, he does say on a number of occasions that it was material he was talking about privately".
This week, lawyers from MGN claimed that Prince Harry is entitled to just £500 compensation.
MGN is being sued by several high-profile people over alleged unlawful information gathering at its titles.
The publisher of titles including The Mirror, Sunday Mirror and Sunday People, is largely contesting the claims, arguing that some have been submitted too late.
During his closing argument, Andrew Green KC, representing the MGN said: "There is only one occasion of admitted unlawful information gathering in respect of the Duke of Sussex, in February 2004."
Green continued: "In this case the Duke of Sussex should be awarded a maximum of £500, given the single invoice naming him concerns inquiries on an isolated occasion, and the small sum on the invoice (£75) suggests inquiries were limited."
Earlier this month, Prince Harry admitted that he decided to pursue legal cases against tabloid newspapers after a chance meeting in France.
The Duke of Sussex was grilled on when he first sought advice about a possible claim against MGN.
LATEST DEVELOPMENTS:
Prince Harry told the High Court that he bumped into David Sherborne in France around 2018.
PA
Prince Harry told the High Court that he bumped into David Sherborne in France around 2018.
Harry said: "I didn’t go to them, I bumped into Mr Sherborne in France. It’s in my book."
The Duke of Sussex said that before he spoke to lawyers he had no concerns over any particular articles being the result of unlawful activity.
Harry said: "No, I was never shown anything. It was all contained within the palace."
He added regarding his conversations with the lawyers: "I think it was a discussion about how to find a way to stop the abuse and intrusion that was coming against me and my wife…without relying on the institution’s lawyers."